LU-9085 llstat: don't use a hash as a reference

LU-9085 llstat: don't use a hash as a reference

This patch is to fix "Using a hash as a reference is deprecated"
in llstat file. In the newer perl version, we should use "$xxx"
instead of "%xxx" for a hash reference.

Signed-off-by: Emoly Liu <emoly.liu@intel.com>
Change-Id: I67a1d1e365076b412550de775b115ac373589c60
Reviewed-on: https://review.whamcloud.com/25320
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Jian Yu <jian.yu@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>